Deep in the ocean floor scientists find life buried for millions of years

There’s a truly fascinating research paper in the journal Science just out today.

Scientists have drilled into the bottom of the Pacific Ocean, generally along the equator and into the North Pacific Gyre, to bring back samples of the clay there. They brought brought cores of sediment up to 90-feet deep into the seafloor.

And they found life. Lots of it. That’s not surprising, as it’s estimated that about 90 percent of Earth’s single-celled organisms live buried beneath the sea floor.

But these scientists didn’t just find life near the top of the cores, but deep in them, in ancient sediment.

Calm seas on the equator. (Science/AAAS)

Sediment builds up on the ocean floor over time, about 1 millimeter per 1,000 years. So the bottom of these cores represents sediment that tens of millions of years old.

In their research paper (see abstract) the scientists describe the discovery of bacteria deep in the cores that are still active, if barely. The organisms have enough oxygen to keep their membrane intact (which requires energy) and to keep enzymes and DNA functioning.

Here’s the amazing part: this life is subsisting in sediment that has not received outside food from the world since dinosaurs roamed the Earth, for a span of at least 86 million years.

Here, then, is life previously unknown to us, possibly subsisting at the minimum energy needed for life.